xref: /openbmc/linux/drivers/hwmon/nct7904.c (revision 15e3ae36)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * nct7904.c - driver for Nuvoton NCT7904D.
4  *
5  * Copyright (c) 2015 Kontron
6  * Author: Vadim V. Vlasov <vvlasov@dev.rtsoft.ru>
7  *
8  * Copyright (c) 2019 Advantech
9  * Author: Amy.Shih <amy.shih@advantech.com.tw>
10  *
11  * Supports the following chips:
12  *
13  * Chip        #vin  #fan  #pwm  #temp  #dts  chip ID
14  * nct7904d     20    12    4     5      8    0xc5
15  */
16 
17 #include <linux/module.h>
18 #include <linux/device.h>
19 #include <linux/init.h>
20 #include <linux/i2c.h>
21 #include <linux/mutex.h>
22 #include <linux/hwmon.h>
23 
24 #define VENDOR_ID_REG		0x7A	/* Any bank */
25 #define NUVOTON_ID		0x50
26 #define CHIP_ID_REG		0x7B	/* Any bank */
27 #define NCT7904_ID		0xC5
28 #define DEVICE_ID_REG		0x7C	/* Any bank */
29 
30 #define BANK_SEL_REG		0xFF
31 #define BANK_0			0x00
32 #define BANK_1			0x01
33 #define BANK_2			0x02
34 #define BANK_3			0x03
35 #define BANK_4			0x04
36 #define BANK_MAX		0x04
37 
38 #define FANIN_MAX		12	/* Counted from 1 */
39 #define VSEN_MAX		21	/* VSEN1..14, 3VDD, VBAT, V3VSB,
40 					   LTD (not a voltage), VSEN17..19 */
41 #define FANCTL_MAX		4	/* Counted from 1 */
42 #define TCPU_MAX		8	/* Counted from 1 */
43 #define TEMP_MAX		4	/* Counted from 1 */
44 
45 #define VT_ADC_CTRL0_REG	0x20	/* Bank 0 */
46 #define VT_ADC_CTRL1_REG	0x21	/* Bank 0 */
47 #define VT_ADC_CTRL2_REG	0x22	/* Bank 0 */
48 #define FANIN_CTRL0_REG		0x24
49 #define FANIN_CTRL1_REG		0x25
50 #define DTS_T_CTRL0_REG		0x26
51 #define DTS_T_CTRL1_REG		0x27
52 #define VT_ADC_MD_REG		0x2E
53 
54 #define VSEN1_HV_LL_REG		0x02	/* Bank 1; 2 regs (HV/LV) per sensor */
55 #define VSEN1_LV_LL_REG		0x03	/* Bank 1; 2 regs (HV/LV) per sensor */
56 #define VSEN1_HV_HL_REG		0x00	/* Bank 1; 2 regs (HV/LV) per sensor */
57 #define VSEN1_LV_HL_REG		0x01	/* Bank 1; 2 regs (HV/LV) per sensor */
58 #define SMI_STS1_REG		0xC1	/* Bank 0; SMI Status Register */
59 #define SMI_STS3_REG		0xC3	/* Bank 0; SMI Status Register */
60 #define SMI_STS5_REG		0xC5	/* Bank 0; SMI Status Register */
61 #define SMI_STS7_REG		0xC7	/* Bank 0; SMI Status Register */
62 #define SMI_STS8_REG		0xC8	/* Bank 0; SMI Status Register */
63 
64 #define VSEN1_HV_REG		0x40	/* Bank 0; 2 regs (HV/LV) per sensor */
65 #define TEMP_CH1_HV_REG		0x42	/* Bank 0; same as VSEN2_HV */
66 #define LTD_HV_REG		0x62	/* Bank 0; 2 regs in VSEN range */
67 #define LTD_HV_HL_REG		0x44	/* Bank 1; 1 reg for LTD */
68 #define LTD_LV_HL_REG		0x45	/* Bank 1; 1 reg for LTD */
69 #define LTD_HV_LL_REG		0x46	/* Bank 1; 1 reg for LTD */
70 #define LTD_LV_LL_REG		0x47	/* Bank 1; 1 reg for LTD */
71 #define TEMP_CH1_CH_REG		0x05	/* Bank 1; 1 reg for LTD */
72 #define TEMP_CH1_W_REG		0x06	/* Bank 1; 1 reg for LTD */
73 #define TEMP_CH1_WH_REG		0x07	/* Bank 1; 1 reg for LTD */
74 #define TEMP_CH1_C_REG		0x04	/* Bank 1; 1 reg per sensor */
75 #define DTS_T_CPU1_C_REG	0x90	/* Bank 1; 1 reg per sensor */
76 #define DTS_T_CPU1_CH_REG	0x91	/* Bank 1; 1 reg per sensor */
77 #define DTS_T_CPU1_W_REG	0x92	/* Bank 1; 1 reg per sensor */
78 #define DTS_T_CPU1_WH_REG	0x93	/* Bank 1; 1 reg per sensor */
79 #define FANIN1_HV_REG		0x80	/* Bank 0; 2 regs (HV/LV) per sensor */
80 #define FANIN1_HV_HL_REG	0x60	/* Bank 1; 2 regs (HV/LV) per sensor */
81 #define FANIN1_LV_HL_REG	0x61	/* Bank 1; 2 regs (HV/LV) per sensor */
82 #define T_CPU1_HV_REG		0xA0	/* Bank 0; 2 regs (HV/LV) per sensor */
83 
84 #define PRTS_REG		0x03	/* Bank 2 */
85 #define PFE_REG			0x00	/* Bank 2; PECI Function Enable */
86 #define TSI_CTRL_REG		0x50	/* Bank 2; TSI Control Register */
87 #define FANCTL1_FMR_REG		0x00	/* Bank 3; 1 reg per channel */
88 #define FANCTL1_OUT_REG		0x10	/* Bank 3; 1 reg per channel */
89 
90 #define VOLT_MONITOR_MODE	0x0
91 #define THERMAL_DIODE_MODE	0x1
92 #define THERMISTOR_MODE		0x3
93 
94 #define ENABLE_TSI	BIT(1)
95 
96 static const unsigned short normal_i2c[] = {
97 	0x2d, 0x2e, I2C_CLIENT_END
98 };
99 
100 struct nct7904_data {
101 	struct i2c_client *client;
102 	struct mutex bank_lock;
103 	int bank_sel;
104 	u32 fanin_mask;
105 	u32 vsen_mask;
106 	u32 tcpu_mask;
107 	u8 fan_mode[FANCTL_MAX];
108 	u8 enable_dts;
109 	u8 has_dts;
110 	u8 temp_mode; /* 0: TR mode, 1: TD mode */
111 	u8 fan_alarm[2];
112 	u8 vsen_alarm[3];
113 };
114 
115 /* Access functions */
116 static int nct7904_bank_lock(struct nct7904_data *data, unsigned int bank)
117 {
118 	int ret;
119 
120 	mutex_lock(&data->bank_lock);
121 	if (data->bank_sel == bank)
122 		return 0;
123 	ret = i2c_smbus_write_byte_data(data->client, BANK_SEL_REG, bank);
124 	if (ret == 0)
125 		data->bank_sel = bank;
126 	else
127 		data->bank_sel = -1;
128 	return ret;
129 }
130 
131 static inline void nct7904_bank_release(struct nct7904_data *data)
132 {
133 	mutex_unlock(&data->bank_lock);
134 }
135 
136 /* Read 1-byte register. Returns unsigned reg or -ERRNO on error. */
137 static int nct7904_read_reg(struct nct7904_data *data,
138 			    unsigned int bank, unsigned int reg)
139 {
140 	struct i2c_client *client = data->client;
141 	int ret;
142 
143 	ret = nct7904_bank_lock(data, bank);
144 	if (ret == 0)
145 		ret = i2c_smbus_read_byte_data(client, reg);
146 
147 	nct7904_bank_release(data);
148 	return ret;
149 }
150 
151 /*
152  * Read 2-byte register. Returns register in big-endian format or
153  * -ERRNO on error.
154  */
155 static int nct7904_read_reg16(struct nct7904_data *data,
156 			      unsigned int bank, unsigned int reg)
157 {
158 	struct i2c_client *client = data->client;
159 	int ret, hi;
160 
161 	ret = nct7904_bank_lock(data, bank);
162 	if (ret == 0) {
163 		ret = i2c_smbus_read_byte_data(client, reg);
164 		if (ret >= 0) {
165 			hi = ret;
166 			ret = i2c_smbus_read_byte_data(client, reg + 1);
167 			if (ret >= 0)
168 				ret |= hi << 8;
169 		}
170 	}
171 
172 	nct7904_bank_release(data);
173 	return ret;
174 }
175 
176 /* Write 1-byte register. Returns 0 or -ERRNO on error. */
177 static int nct7904_write_reg(struct nct7904_data *data,
178 			     unsigned int bank, unsigned int reg, u8 val)
179 {
180 	struct i2c_client *client = data->client;
181 	int ret;
182 
183 	ret = nct7904_bank_lock(data, bank);
184 	if (ret == 0)
185 		ret = i2c_smbus_write_byte_data(client, reg, val);
186 
187 	nct7904_bank_release(data);
188 	return ret;
189 }
190 
191 static int nct7904_read_fan(struct device *dev, u32 attr, int channel,
192 			    long *val)
193 {
194 	struct nct7904_data *data = dev_get_drvdata(dev);
195 	unsigned int cnt, rpm;
196 	int ret;
197 
198 	switch (attr) {
199 	case hwmon_fan_input:
200 		ret = nct7904_read_reg16(data, BANK_0,
201 					 FANIN1_HV_REG + channel * 2);
202 		if (ret < 0)
203 			return ret;
204 		cnt = ((ret & 0xff00) >> 3) | (ret & 0x1f);
205 		if (cnt == 0x1fff)
206 			rpm = 0;
207 		else
208 			rpm = 1350000 / cnt;
209 		*val = rpm;
210 		return 0;
211 	case hwmon_fan_min:
212 		ret = nct7904_read_reg16(data, BANK_1,
213 					 FANIN1_HV_HL_REG + channel * 2);
214 		if (ret < 0)
215 			return ret;
216 		cnt = ((ret & 0xff00) >> 3) | (ret & 0x1f);
217 		if (cnt == 0x1fff)
218 			rpm = 0;
219 		else
220 			rpm = 1350000 / cnt;
221 		*val = rpm;
222 		return 0;
223 	case hwmon_fan_alarm:
224 		ret = nct7904_read_reg(data, BANK_0,
225 				       SMI_STS5_REG + (channel >> 3));
226 		if (ret < 0)
227 			return ret;
228 		if (!data->fan_alarm[channel >> 3])
229 			data->fan_alarm[channel >> 3] = ret & 0xff;
230 		else
231 			/* If there is new alarm showing up */
232 			data->fan_alarm[channel >> 3] |= (ret & 0xff);
233 		*val = (data->fan_alarm[channel >> 3] >> (channel & 0x07)) & 1;
234 		/* Needs to clean the alarm if alarm existing */
235 		if (*val)
236 			data->fan_alarm[channel >> 3] ^= 1 << (channel & 0x07);
237 		return 0;
238 	default:
239 		return -EOPNOTSUPP;
240 	}
241 }
242 
243 static umode_t nct7904_fan_is_visible(const void *_data, u32 attr, int channel)
244 {
245 	const struct nct7904_data *data = _data;
246 
247 	switch (attr) {
248 	case hwmon_fan_input:
249 	case hwmon_fan_alarm:
250 		if (data->fanin_mask & (1 << channel))
251 			return 0444;
252 		break;
253 	case hwmon_fan_min:
254 		if (data->fanin_mask & (1 << channel))
255 			return 0644;
256 		break;
257 	default:
258 		break;
259 	}
260 
261 	return 0;
262 }
263 
264 static u8 nct7904_chan_to_index[] = {
265 	0,	/* Not used */
266 	0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
267 	18, 19, 20, 16
268 };
269 
270 static int nct7904_read_in(struct device *dev, u32 attr, int channel,
271 			   long *val)
272 {
273 	struct nct7904_data *data = dev_get_drvdata(dev);
274 	int ret, volt, index;
275 
276 	index = nct7904_chan_to_index[channel];
277 
278 	switch (attr) {
279 	case hwmon_in_input:
280 		ret = nct7904_read_reg16(data, BANK_0,
281 					 VSEN1_HV_REG + index * 2);
282 		if (ret < 0)
283 			return ret;
284 		volt = ((ret & 0xff00) >> 5) | (ret & 0x7);
285 		if (index < 14)
286 			volt *= 2; /* 0.002V scale */
287 		else
288 			volt *= 6; /* 0.006V scale */
289 		*val = volt;
290 		return 0;
291 	case hwmon_in_min:
292 		ret = nct7904_read_reg16(data, BANK_1,
293 					 VSEN1_HV_LL_REG + index * 4);
294 		if (ret < 0)
295 			return ret;
296 		volt = ((ret & 0xff00) >> 5) | (ret & 0x7);
297 		if (index < 14)
298 			volt *= 2; /* 0.002V scale */
299 		else
300 			volt *= 6; /* 0.006V scale */
301 		*val = volt;
302 		return 0;
303 	case hwmon_in_max:
304 		ret = nct7904_read_reg16(data, BANK_1,
305 					 VSEN1_HV_HL_REG + index * 4);
306 		if (ret < 0)
307 			return ret;
308 		volt = ((ret & 0xff00) >> 5) | (ret & 0x7);
309 		if (index < 14)
310 			volt *= 2; /* 0.002V scale */
311 		else
312 			volt *= 6; /* 0.006V scale */
313 		*val = volt;
314 		return 0;
315 	case hwmon_in_alarm:
316 		ret = nct7904_read_reg(data, BANK_0,
317 				       SMI_STS1_REG + (index >> 3));
318 		if (ret < 0)
319 			return ret;
320 		if (!data->vsen_alarm[index >> 3])
321 			data->vsen_alarm[index >> 3] = ret & 0xff;
322 		else
323 			/* If there is new alarm showing up */
324 			data->vsen_alarm[index >> 3] |= (ret & 0xff);
325 		*val = (data->vsen_alarm[index >> 3] >> (index & 0x07)) & 1;
326 		/* Needs to clean the alarm if alarm existing */
327 		if (*val)
328 			data->vsen_alarm[index >> 3] ^= 1 << (index & 0x07);
329 		return 0;
330 	default:
331 		return -EOPNOTSUPP;
332 	}
333 }
334 
335 static umode_t nct7904_in_is_visible(const void *_data, u32 attr, int channel)
336 {
337 	const struct nct7904_data *data = _data;
338 	int index = nct7904_chan_to_index[channel];
339 
340 	switch (attr) {
341 	case hwmon_in_input:
342 	case hwmon_in_alarm:
343 		if (channel > 0 && (data->vsen_mask & BIT(index)))
344 			return 0444;
345 		break;
346 	case hwmon_in_min:
347 	case hwmon_in_max:
348 		if (channel > 0 && (data->vsen_mask & BIT(index)))
349 			return 0644;
350 		break;
351 	default:
352 		break;
353 	}
354 
355 	return 0;
356 }
357 
358 static int nct7904_read_temp(struct device *dev, u32 attr, int channel,
359 			     long *val)
360 {
361 	struct nct7904_data *data = dev_get_drvdata(dev);
362 	int ret, temp;
363 	unsigned int reg1, reg2, reg3;
364 
365 	switch (attr) {
366 	case hwmon_temp_input:
367 		if (channel == 4)
368 			ret = nct7904_read_reg16(data, BANK_0, LTD_HV_REG);
369 		else if (channel < 5)
370 			ret = nct7904_read_reg16(data, BANK_0,
371 						 TEMP_CH1_HV_REG + channel * 4);
372 		else
373 			ret = nct7904_read_reg16(data, BANK_0,
374 						 T_CPU1_HV_REG + (channel - 5)
375 						 * 2);
376 		if (ret < 0)
377 			return ret;
378 		temp = ((ret & 0xff00) >> 5) | (ret & 0x7);
379 		*val = sign_extend32(temp, 10) * 125;
380 		return 0;
381 	case hwmon_temp_alarm:
382 		if (channel == 4) {
383 			ret = nct7904_read_reg(data, BANK_0,
384 					       SMI_STS3_REG);
385 			if (ret < 0)
386 				return ret;
387 			*val = (ret >> 1) & 1;
388 		} else if (channel < 4) {
389 			ret = nct7904_read_reg(data, BANK_0,
390 					       SMI_STS1_REG);
391 			if (ret < 0)
392 				return ret;
393 			*val = (ret >> (((channel * 2) + 1) & 0x07)) & 1;
394 		} else {
395 			if ((channel - 5) < 4) {
396 				ret = nct7904_read_reg(data, BANK_0,
397 						       SMI_STS7_REG +
398 						       ((channel - 5) >> 3));
399 				if (ret < 0)
400 					return ret;
401 				*val = (ret >> ((channel - 5) & 0x07)) & 1;
402 			} else {
403 				ret = nct7904_read_reg(data, BANK_0,
404 						       SMI_STS8_REG +
405 						       ((channel - 5) >> 3));
406 				if (ret < 0)
407 					return ret;
408 				*val = (ret >> (((channel - 5) & 0x07) - 4))
409 							& 1;
410 			}
411 		}
412 		return 0;
413 	case hwmon_temp_type:
414 		if (channel < 5) {
415 			if ((data->tcpu_mask >> channel) & 0x01) {
416 				if ((data->temp_mode >> channel) & 0x01)
417 					*val = 3; /* TD */
418 				else
419 					*val = 4; /* TR */
420 			} else {
421 				*val = 0;
422 			}
423 		} else {
424 			if ((data->has_dts >> (channel - 5)) & 0x01) {
425 				if (data->enable_dts & ENABLE_TSI)
426 					*val = 5; /* TSI */
427 				else
428 					*val = 6; /* PECI */
429 			} else {
430 				*val = 0;
431 			}
432 		}
433 		return 0;
434 	case hwmon_temp_max:
435 		reg1 = LTD_HV_LL_REG;
436 		reg2 = TEMP_CH1_W_REG;
437 		reg3 = DTS_T_CPU1_W_REG;
438 		break;
439 	case hwmon_temp_max_hyst:
440 		reg1 = LTD_LV_LL_REG;
441 		reg2 = TEMP_CH1_WH_REG;
442 		reg3 = DTS_T_CPU1_WH_REG;
443 		break;
444 	case hwmon_temp_crit:
445 		reg1 = LTD_HV_HL_REG;
446 		reg2 = TEMP_CH1_C_REG;
447 		reg3 = DTS_T_CPU1_C_REG;
448 		break;
449 	case hwmon_temp_crit_hyst:
450 		reg1 = LTD_LV_HL_REG;
451 		reg2 = TEMP_CH1_CH_REG;
452 		reg3 = DTS_T_CPU1_CH_REG;
453 		break;
454 	default:
455 		return -EOPNOTSUPP;
456 	}
457 
458 	if (channel == 4)
459 		ret = nct7904_read_reg(data, BANK_1, reg1);
460 	else if (channel < 5)
461 		ret = nct7904_read_reg(data, BANK_1,
462 				       reg2 + channel * 8);
463 	else
464 		ret = nct7904_read_reg(data, BANK_1,
465 				       reg3 + (channel - 5) * 4);
466 
467 	if (ret < 0)
468 		return ret;
469 	*val = ret * 1000;
470 	return 0;
471 }
472 
473 static umode_t nct7904_temp_is_visible(const void *_data, u32 attr, int channel)
474 {
475 	const struct nct7904_data *data = _data;
476 
477 	switch (attr) {
478 	case hwmon_temp_input:
479 	case hwmon_temp_alarm:
480 	case hwmon_temp_type:
481 		if (channel < 5) {
482 			if (data->tcpu_mask & BIT(channel))
483 				return 0444;
484 		} else {
485 			if (data->has_dts & BIT(channel - 5))
486 				return 0444;
487 		}
488 		break;
489 	case hwmon_temp_max:
490 	case hwmon_temp_max_hyst:
491 	case hwmon_temp_crit:
492 	case hwmon_temp_crit_hyst:
493 		if (channel < 5) {
494 			if (data->tcpu_mask & BIT(channel))
495 				return 0644;
496 		} else {
497 			if (data->has_dts & BIT(channel - 5))
498 				return 0644;
499 		}
500 		break;
501 	default:
502 		break;
503 	}
504 
505 	return 0;
506 }
507 
508 static int nct7904_read_pwm(struct device *dev, u32 attr, int channel,
509 			    long *val)
510 {
511 	struct nct7904_data *data = dev_get_drvdata(dev);
512 	int ret;
513 
514 	switch (attr) {
515 	case hwmon_pwm_input:
516 		ret = nct7904_read_reg(data, BANK_3, FANCTL1_OUT_REG + channel);
517 		if (ret < 0)
518 			return ret;
519 		*val = ret;
520 		return 0;
521 	case hwmon_pwm_enable:
522 		ret = nct7904_read_reg(data, BANK_3, FANCTL1_FMR_REG + channel);
523 		if (ret < 0)
524 			return ret;
525 
526 		*val = ret ? 2 : 1;
527 		return 0;
528 	default:
529 		return -EOPNOTSUPP;
530 	}
531 }
532 
533 static int nct7904_write_temp(struct device *dev, u32 attr, int channel,
534 			      long val)
535 {
536 	struct nct7904_data *data = dev_get_drvdata(dev);
537 	int ret;
538 	unsigned int reg1, reg2, reg3;
539 
540 	val = clamp_val(val / 1000, -128, 127);
541 
542 	switch (attr) {
543 	case hwmon_temp_max:
544 		reg1 = LTD_HV_LL_REG;
545 		reg2 = TEMP_CH1_W_REG;
546 		reg3 = DTS_T_CPU1_W_REG;
547 		break;
548 	case hwmon_temp_max_hyst:
549 		reg1 = LTD_LV_LL_REG;
550 		reg2 = TEMP_CH1_WH_REG;
551 		reg3 = DTS_T_CPU1_WH_REG;
552 		break;
553 	case hwmon_temp_crit:
554 		reg1 = LTD_HV_HL_REG;
555 		reg2 = TEMP_CH1_C_REG;
556 		reg3 = DTS_T_CPU1_C_REG;
557 		break;
558 	case hwmon_temp_crit_hyst:
559 		reg1 = LTD_LV_HL_REG;
560 		reg2 = TEMP_CH1_CH_REG;
561 		reg3 = DTS_T_CPU1_CH_REG;
562 		break;
563 	default:
564 		return -EOPNOTSUPP;
565 	}
566 	if (channel == 4)
567 		ret = nct7904_write_reg(data, BANK_1, reg1, val);
568 	else if (channel < 5)
569 		ret = nct7904_write_reg(data, BANK_1,
570 					reg2 + channel * 8, val);
571 	else
572 		ret = nct7904_write_reg(data, BANK_1,
573 					reg3 + (channel - 5) * 4, val);
574 
575 	return ret;
576 }
577 
578 static int nct7904_write_fan(struct device *dev, u32 attr, int channel,
579 			     long val)
580 {
581 	struct nct7904_data *data = dev_get_drvdata(dev);
582 	int ret;
583 	u8 tmp;
584 
585 	switch (attr) {
586 	case hwmon_fan_min:
587 		if (val <= 0)
588 			return -EINVAL;
589 
590 		val = clamp_val(DIV_ROUND_CLOSEST(1350000, val), 1, 0x1fff);
591 		tmp = (val >> 5) & 0xff;
592 		ret = nct7904_write_reg(data, BANK_1,
593 					FANIN1_HV_HL_REG + channel * 2, tmp);
594 		if (ret < 0)
595 			return ret;
596 		tmp = val & 0x1f;
597 		ret = nct7904_write_reg(data, BANK_1,
598 					FANIN1_LV_HL_REG + channel * 2, tmp);
599 		return ret;
600 	default:
601 		return -EOPNOTSUPP;
602 	}
603 }
604 
605 static int nct7904_write_in(struct device *dev, u32 attr, int channel,
606 			    long val)
607 {
608 	struct nct7904_data *data = dev_get_drvdata(dev);
609 	int ret, index, tmp;
610 
611 	index = nct7904_chan_to_index[channel];
612 
613 	if (index < 14)
614 		val = val / 2; /* 0.002V scale */
615 	else
616 		val = val / 6; /* 0.006V scale */
617 
618 	val = clamp_val(val, 0, 0x7ff);
619 
620 	switch (attr) {
621 	case hwmon_in_min:
622 		tmp = nct7904_read_reg(data, BANK_1,
623 				       VSEN1_LV_LL_REG + index * 4);
624 		if (tmp < 0)
625 			return tmp;
626 		tmp &= ~0x7;
627 		tmp |= val & 0x7;
628 		ret = nct7904_write_reg(data, BANK_1,
629 					VSEN1_LV_LL_REG + index * 4, tmp);
630 		if (ret < 0)
631 			return ret;
632 		tmp = nct7904_read_reg(data, BANK_1,
633 				       VSEN1_HV_LL_REG + index * 4);
634 		if (tmp < 0)
635 			return tmp;
636 		tmp = (val >> 3) & 0xff;
637 		ret = nct7904_write_reg(data, BANK_1,
638 					VSEN1_HV_LL_REG + index * 4, tmp);
639 		return ret;
640 	case hwmon_in_max:
641 		tmp = nct7904_read_reg(data, BANK_1,
642 				       VSEN1_LV_HL_REG + index * 4);
643 		if (tmp < 0)
644 			return tmp;
645 		tmp &= ~0x7;
646 		tmp |= val & 0x7;
647 		ret = nct7904_write_reg(data, BANK_1,
648 					VSEN1_LV_HL_REG + index * 4, tmp);
649 		if (ret < 0)
650 			return ret;
651 		tmp = nct7904_read_reg(data, BANK_1,
652 				       VSEN1_HV_HL_REG + index * 4);
653 		if (tmp < 0)
654 			return tmp;
655 		tmp = (val >> 3) & 0xff;
656 		ret = nct7904_write_reg(data, BANK_1,
657 					VSEN1_HV_HL_REG + index * 4, tmp);
658 		return ret;
659 	default:
660 		return -EOPNOTSUPP;
661 	}
662 }
663 
664 static int nct7904_write_pwm(struct device *dev, u32 attr, int channel,
665 			     long val)
666 {
667 	struct nct7904_data *data = dev_get_drvdata(dev);
668 	int ret;
669 
670 	switch (attr) {
671 	case hwmon_pwm_input:
672 		if (val < 0 || val > 255)
673 			return -EINVAL;
674 		ret = nct7904_write_reg(data, BANK_3, FANCTL1_OUT_REG + channel,
675 					val);
676 		return ret;
677 	case hwmon_pwm_enable:
678 		if (val < 1 || val > 2 ||
679 		    (val == 2 && !data->fan_mode[channel]))
680 			return -EINVAL;
681 		ret = nct7904_write_reg(data, BANK_3, FANCTL1_FMR_REG + channel,
682 					val == 2 ? data->fan_mode[channel] : 0);
683 		return ret;
684 	default:
685 		return -EOPNOTSUPP;
686 	}
687 }
688 
689 static umode_t nct7904_pwm_is_visible(const void *_data, u32 attr, int channel)
690 {
691 	switch (attr) {
692 	case hwmon_pwm_input:
693 	case hwmon_pwm_enable:
694 		return 0644;
695 	default:
696 		return 0;
697 	}
698 }
699 
700 static int nct7904_read(struct device *dev, enum hwmon_sensor_types type,
701 			u32 attr, int channel, long *val)
702 {
703 	switch (type) {
704 	case hwmon_in:
705 		return nct7904_read_in(dev, attr, channel, val);
706 	case hwmon_fan:
707 		return nct7904_read_fan(dev, attr, channel, val);
708 	case hwmon_pwm:
709 		return nct7904_read_pwm(dev, attr, channel, val);
710 	case hwmon_temp:
711 		return nct7904_read_temp(dev, attr, channel, val);
712 	default:
713 		return -EOPNOTSUPP;
714 	}
715 }
716 
717 static int nct7904_write(struct device *dev, enum hwmon_sensor_types type,
718 			 u32 attr, int channel, long val)
719 {
720 	switch (type) {
721 	case hwmon_in:
722 		return nct7904_write_in(dev, attr, channel, val);
723 	case hwmon_fan:
724 		return nct7904_write_fan(dev, attr, channel, val);
725 	case hwmon_pwm:
726 		return nct7904_write_pwm(dev, attr, channel, val);
727 	case hwmon_temp:
728 		return nct7904_write_temp(dev, attr, channel, val);
729 	default:
730 		return -EOPNOTSUPP;
731 	}
732 }
733 
734 static umode_t nct7904_is_visible(const void *data,
735 				  enum hwmon_sensor_types type,
736 				  u32 attr, int channel)
737 {
738 	switch (type) {
739 	case hwmon_in:
740 		return nct7904_in_is_visible(data, attr, channel);
741 	case hwmon_fan:
742 		return nct7904_fan_is_visible(data, attr, channel);
743 	case hwmon_pwm:
744 		return nct7904_pwm_is_visible(data, attr, channel);
745 	case hwmon_temp:
746 		return nct7904_temp_is_visible(data, attr, channel);
747 	default:
748 		return 0;
749 	}
750 }
751 
752 /* Return 0 if detection is successful, -ENODEV otherwise */
753 static int nct7904_detect(struct i2c_client *client,
754 			  struct i2c_board_info *info)
755 {
756 	struct i2c_adapter *adapter = client->adapter;
757 
758 	if (!i2c_check_functionality(adapter,
759 				     I2C_FUNC_SMBUS_READ_BYTE |
760 				     I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
761 		return -ENODEV;
762 
763 	/* Determine the chip type. */
764 	if (i2c_smbus_read_byte_data(client, VENDOR_ID_REG) != NUVOTON_ID ||
765 	    i2c_smbus_read_byte_data(client, CHIP_ID_REG) != NCT7904_ID ||
766 	    (i2c_smbus_read_byte_data(client, DEVICE_ID_REG) & 0xf0) != 0x50 ||
767 	    (i2c_smbus_read_byte_data(client, BANK_SEL_REG) & 0xf8) != 0x00)
768 		return -ENODEV;
769 
770 	strlcpy(info->type, "nct7904", I2C_NAME_SIZE);
771 
772 	return 0;
773 }
774 
775 static const struct hwmon_channel_info *nct7904_info[] = {
776 	HWMON_CHANNEL_INFO(in,
777 			   /* dummy, skipped in is_visible */
778 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
779 			   HWMON_I_ALARM,
780 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
781 			   HWMON_I_ALARM,
782 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
783 			   HWMON_I_ALARM,
784 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
785 			   HWMON_I_ALARM,
786 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
787 			   HWMON_I_ALARM,
788 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
789 			   HWMON_I_ALARM,
790 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
791 			   HWMON_I_ALARM,
792 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
793 			   HWMON_I_ALARM,
794 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
795 			   HWMON_I_ALARM,
796 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
797 			   HWMON_I_ALARM,
798 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
799 			   HWMON_I_ALARM,
800 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
801 			   HWMON_I_ALARM,
802 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
803 			   HWMON_I_ALARM,
804 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
805 			   HWMON_I_ALARM,
806 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
807 			   HWMON_I_ALARM,
808 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
809 			   HWMON_I_ALARM,
810 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
811 			   HWMON_I_ALARM,
812 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
813 			   HWMON_I_ALARM,
814 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
815 			   HWMON_I_ALARM,
816 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
817 			   HWMON_I_ALARM,
818 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
819 			   HWMON_I_ALARM),
820 	HWMON_CHANNEL_INFO(fan,
821 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
822 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
823 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
824 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
825 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
826 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
827 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
828 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
829 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
830 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
831 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
832 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM),
833 	HWMON_CHANNEL_INFO(pwm,
834 			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
835 			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
836 			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
837 			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE),
838 	HWMON_CHANNEL_INFO(temp,
839 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
840 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
841 			   HWMON_T_CRIT_HYST,
842 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
843 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
844 			   HWMON_T_CRIT_HYST,
845 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
846 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
847 			   HWMON_T_CRIT_HYST,
848 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
849 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
850 			   HWMON_T_CRIT_HYST,
851 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
852 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
853 			   HWMON_T_CRIT_HYST,
854 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
855 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
856 			   HWMON_T_CRIT_HYST,
857 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
858 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
859 			   HWMON_T_CRIT_HYST,
860 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
861 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
862 			   HWMON_T_CRIT_HYST,
863 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
864 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
865 			   HWMON_T_CRIT_HYST,
866 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
867 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
868 			   HWMON_T_CRIT_HYST,
869 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
870 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
871 			   HWMON_T_CRIT_HYST,
872 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
873 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
874 			   HWMON_T_CRIT_HYST,
875 			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
876 			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
877 			   HWMON_T_CRIT_HYST),
878 	NULL
879 };
880 
881 static const struct hwmon_ops nct7904_hwmon_ops = {
882 	.is_visible = nct7904_is_visible,
883 	.read = nct7904_read,
884 	.write = nct7904_write,
885 };
886 
887 static const struct hwmon_chip_info nct7904_chip_info = {
888 	.ops = &nct7904_hwmon_ops,
889 	.info = nct7904_info,
890 };
891 
892 static int nct7904_probe(struct i2c_client *client,
893 			 const struct i2c_device_id *id)
894 {
895 	struct nct7904_data *data;
896 	struct device *hwmon_dev;
897 	struct device *dev = &client->dev;
898 	int ret, i;
899 	u32 mask;
900 	u8 val, bit;
901 
902 	data = devm_kzalloc(dev, sizeof(struct nct7904_data), GFP_KERNEL);
903 	if (!data)
904 		return -ENOMEM;
905 
906 	data->client = client;
907 	mutex_init(&data->bank_lock);
908 	data->bank_sel = -1;
909 
910 	/* Setup sensor groups. */
911 	/* FANIN attributes */
912 	ret = nct7904_read_reg16(data, BANK_0, FANIN_CTRL0_REG);
913 	if (ret < 0)
914 		return ret;
915 	data->fanin_mask = (ret >> 8) | ((ret & 0xff) << 8);
916 
917 	/*
918 	 * VSEN attributes
919 	 *
920 	 * Note: voltage sensors overlap with external temperature
921 	 * sensors. So, if we ever decide to support the latter
922 	 * we will have to adjust 'vsen_mask' accordingly.
923 	 */
924 	mask = 0;
925 	ret = nct7904_read_reg16(data, BANK_0, VT_ADC_CTRL0_REG);
926 	if (ret >= 0)
927 		mask = (ret >> 8) | ((ret & 0xff) << 8);
928 	ret = nct7904_read_reg(data, BANK_0, VT_ADC_CTRL2_REG);
929 	if (ret >= 0)
930 		mask |= (ret << 16);
931 	data->vsen_mask = mask;
932 
933 	/* CPU_TEMP attributes */
934 	ret = nct7904_read_reg(data, BANK_0, VT_ADC_CTRL0_REG);
935 	if (ret < 0)
936 		return ret;
937 
938 	if ((ret & 0x6) == 0x6)
939 		data->tcpu_mask |= 1; /* TR1 */
940 	if ((ret & 0x18) == 0x18)
941 		data->tcpu_mask |= 2; /* TR2 */
942 	if ((ret & 0x20) == 0x20)
943 		data->tcpu_mask |= 4; /* TR3 */
944 	if ((ret & 0x80) == 0x80)
945 		data->tcpu_mask |= 8; /* TR4 */
946 
947 	/* LTD */
948 	ret = nct7904_read_reg(data, BANK_0, VT_ADC_CTRL2_REG);
949 	if (ret < 0)
950 		return ret;
951 	if ((ret & 0x02) == 0x02)
952 		data->tcpu_mask |= 0x10;
953 
954 	/* Multi-Function detecting for Volt and TR/TD */
955 	ret = nct7904_read_reg(data, BANK_0, VT_ADC_MD_REG);
956 	if (ret < 0)
957 		return ret;
958 
959 	data->temp_mode = 0;
960 	for (i = 0; i < 4; i++) {
961 		val = (ret >> (i * 2)) & 0x03;
962 		bit = (1 << i);
963 		if (val == VOLT_MONITOR_MODE) {
964 			data->tcpu_mask &= ~bit;
965 		} else if (val == THERMAL_DIODE_MODE && i < 2) {
966 			data->temp_mode |= bit;
967 			data->vsen_mask &= ~(0x06 << (i * 2));
968 		} else if (val == THERMISTOR_MODE) {
969 			data->vsen_mask &= ~(0x02 << (i * 2));
970 		} else {
971 			/* Reserved */
972 			data->tcpu_mask &= ~bit;
973 			data->vsen_mask &= ~(0x06 << (i * 2));
974 		}
975 	}
976 
977 	/* PECI */
978 	ret = nct7904_read_reg(data, BANK_2, PFE_REG);
979 	if (ret < 0)
980 		return ret;
981 	if (ret & 0x80) {
982 		data->enable_dts = 1; /* Enable DTS & PECI */
983 	} else {
984 		ret = nct7904_read_reg(data, BANK_2, TSI_CTRL_REG);
985 		if (ret < 0)
986 			return ret;
987 		if (ret & 0x80)
988 			data->enable_dts = 0x3; /* Enable DTS & TSI */
989 	}
990 
991 	/* Check DTS enable status */
992 	if (data->enable_dts) {
993 		ret = nct7904_read_reg(data, BANK_0, DTS_T_CTRL0_REG);
994 		if (ret < 0)
995 			return ret;
996 		data->has_dts = ret & 0xF;
997 		if (data->enable_dts & ENABLE_TSI) {
998 			ret = nct7904_read_reg(data, BANK_0, DTS_T_CTRL1_REG);
999 			if (ret < 0)
1000 				return ret;
1001 			data->has_dts |= (ret & 0xF) << 4;
1002 		}
1003 	}
1004 
1005 	for (i = 0; i < FANCTL_MAX; i++) {
1006 		ret = nct7904_read_reg(data, BANK_3, FANCTL1_FMR_REG + i);
1007 		if (ret < 0)
1008 			return ret;
1009 		data->fan_mode[i] = ret;
1010 	}
1011 
1012 	hwmon_dev =
1013 		devm_hwmon_device_register_with_info(dev, client->name, data,
1014 						     &nct7904_chip_info, NULL);
1015 	return PTR_ERR_OR_ZERO(hwmon_dev);
1016 }
1017 
1018 static const struct i2c_device_id nct7904_id[] = {
1019 	{"nct7904", 0},
1020 	{}
1021 };
1022 MODULE_DEVICE_TABLE(i2c, nct7904_id);
1023 
1024 static struct i2c_driver nct7904_driver = {
1025 	.class = I2C_CLASS_HWMON,
1026 	.driver = {
1027 		.name = "nct7904",
1028 	},
1029 	.probe = nct7904_probe,
1030 	.id_table = nct7904_id,
1031 	.detect = nct7904_detect,
1032 	.address_list = normal_i2c,
1033 };
1034 
1035 module_i2c_driver(nct7904_driver);
1036 
1037 MODULE_AUTHOR("Vadim V. Vlasov <vvlasov@dev.rtsoft.ru>");
1038 MODULE_DESCRIPTION("Hwmon driver for NUVOTON NCT7904");
1039 MODULE_LICENSE("GPL");
1040